Is it possible to handle an error from a function deferred until exit?

[THV (Thomas Vidal)]

In a console application, I want to call a function that will perform some actions upon exit of the program. I use a defer block to do that. I also want to handle any errors that may arise from this clean-up function, but have discovered that errors cannot be thrown out of a defer body.

Is there a way for me to (a) handle any errors that may arise in this deferred clean-up function, or (b) call the clean-up function on exit in some way other than using defer? In C (where I'm coming from), I would just register the clean-up function with atexit, which would call that function normally allowing the error-handling routines also run normally.

If the answer is just something I overlooked in the documentation, please feel free to point me where I should be looking. Also, I reviewed the following forum thread:

Is it possible to make early exit in do-try-catch block? (Like `guard`)

It would be convenient to have do-try-catch block in "early-exit style". Like: do-guard let encrypted = try cypher.encrypt(bytes) catch let e { print("Encryption error:", e) return // Thank Adrian for reminding } // Massive code send(encrypted) I may be wrong, but it's not implemented yet.

It did not seem to address my question. But it was a helpful read all the same.

Thanks.

[Lantua]

I don't recall cleanup mechanism other than defer. I think the closest would be to use a do-catch block inside that very defer.

[THV (Thomas Vidal)]

Ahh, perfect! I'll try it that way. Thank you so much.